Test JS script file

Selected file: 051null_comparison.js
Compare console.log() outputs in browser and NodeJS.
Notice: Open browser's console in FireBUG!

  1. 001syntax_unicode.js
  2. 010number_DecToHex.js
  3. 011number_HexToDec.js
  4. 012number_toExponential.js
  5. 013number_modulo.js
  6. 014number_division_by_zero.js
  7. 015number_NaN.js
  8. 016number_infinity.js
  9. 017number_isFinite.js
  10. 018number_isNaN.js
  11. 019number_negative_zero.js
  12. 020number_float_rounding_error.js
  13. 030string_htmlTags.js
  14. 030string_multiline.js
  15. 031string_length.js
  16. 032string_concatenate.js
  17. 032string_concatenate2.js
  18. 033string_minus.js
  19. 035stringmethods_charAt.js
  20. 035stringmethods_concate.js
  21. 035stringmethods_indexOf.js
  22. 035stringmethods_match.js
  23. 035stringmethods_match_memory.js
  24. 035stringmethods_replace.js
  25. 035stringmethods_search.js
  26. 035stringmethods_split.js
  27. 035stringmethods_toString.js
  28. 035stringmethods_toUpperCase.js
  29. 035stringmethods_trim.js
  30. 036string_regexTest.js
  31. 040bool_falsy.js
  32. 040bool_truthy.js
  33. 041bool_comparison.js
  34. 042bool_conditional_operator.js
  35. 043bool_logic_operators.js
  36. 044bool_not_exe_function.js
  37. 050null_typeof.js
  38. 051null_comparison.js
  39. 053undefined_var.js
  40. 054ReferenceError.js
  41. 055global_object_browser.js
  42. 055global_object_node.js
  43. 056global_properties_browser.js
  44. 056global_properties_node.js
  45. 057wrapper_object.js
  46. 058wrapper_object_readonly.js
  47. 60object_reference.js

..:: Source code - 051null_comparison.js ::..

/**
 * comparison of null and empty string
 */

console.log(Boolean('' == null)); //false
console.log(Boolean('' === null)); //false
console.log(Boolean(0 === null)); //false
console.log(Boolean({} === null)); //false
console.log(Boolean({} == null)); //false

console.log('--------------');

var x = null;
if (!x) {
 console.log('x is null');
} else {
 console.log('x is not null');
}
 

..:: NodeJS Console - 051null_comparison.js ::..

$ node 051null_comparison.js 
false
false
false
false
false
--------------
x is null

$ps -aux | grep node (list all node processes)
sasa         914  0.4  0.5 1306308 84480 ?       Ssl  Aug04 120:23 node /home/sasa/.pm2/modules/pm2-logrotate/node_modules/pm2-logr
sasa         935  0.6  0.7 11786816 128664 ?     Ssl  Aug04 180:07 node /home/sasa/dex8/dex8-api/starter.js
sasa         938  0.3  0.4 1304976 74300 ?       Ssl  Aug04  95:34 node /home/sasa/regoch/regoch-www/server
sasa         945  0.3  0.4 1299400 66460 ?       Ssl  Aug04  87:17 node /home/sasa/dex8/dex8-panel/server/index.js
sasa         947  0.6  0.6 11825172 104140 ?     Ssl  Aug04 189:00 node /home/sasa/dex8/dex8-www/server/index.js
sasa         966  0.4  0.5 11809232 97392 ?      Ssl  Aug04 130:12 node /home/sasa/mikosoft_hr/www-mikosoft-hr/server/index.js
sasa         980  0.6  0.5 1329944 83000 ?       Ssl  Aug04 166:51 node /home/sasa/mikosoft-info/api-mikosoft-info/starter.js
sasa         997  0.3  0.4 1300684 68020 ?       Ssl  Aug04  88:21 node /home/sasa/mikosoft-info/www-mikosoft-info/server/index.js
sasa        1021  0.3  0.3 1297656 64500 ?       Ssl  Aug04  87:03 node /home/sasa/dex8/dex8-kiosk/server/index.js
sasa        1065  0.5  0.6 11825504 101008 ?     Ssl  Aug04 141:07 node /home/sasa/mikosoft-info/dodo-mikosoft-info/server/index.js
sasa        1074  0.5  0.6 1147628 102548 ?      Ssl  Aug04 142:37 node /home/sasa/voovuu/voovuu-api/starter.js
sasa        1136  0.6  0.9 11863412 159496 ?     Ssl  Aug04 171:55 node /home/sasa/voovuu/voovuu-pub/server/index.js
sasa        1148  0.3  0.4 11794388 77688 ?      Ssl  Aug04  94:34 node /home/sasa/@mikosoft/dodo-examples/server/index.js
sasa        1197  0.3  0.3 1099116 62860 ?       Ssl  Aug04  89:55 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1199  0.3  0.3 1099872 64028 ?       Ssl  Aug04  89:24 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1308  0.3  0.3 1099616 64108 ?       Ssl  Aug04  89:48 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1325  0.3  0.3 1099360 63720 ?       Ssl  Aug04  89:45 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1393  0.6  0.7 22314068 130392 ?     Ssl  Aug04 183:47 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1395  0.3  0.3 1099884 64072 ?       Ssl  Aug04  90:00 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1489  0.3  0.3 1099360 63876 ?       Ssl  Aug04  90:05 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1496  0.3  0.3 1100128 64644 ?       Ssl  Aug04  89:30 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1607  0.3  0.3 1099104 63672 ?       Ssl  Aug04  89:43 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1608  0.3  0.3 1099616 64212 ?       Ssl  Aug04  89:13 node /home/sasa/dex8/dex8-worker/starter.js
sasa        1686  0.5  0.6 11812464 110388 ?     Ssl  Aug04 142:42 node /home/sasa/mikosoft-info/crypto-mikosoft-info/server/index.
sasa     1371685  0.3  0.4 11795988 81604 ?      Ssl  Aug16  35:13 node /home/sasa/mikosoft-info/solar-wind-energy/server/index.js
sasa     1460918  0.3  0.3 1298600 63756 ?       Ssl  Aug17  31:12 node /home/sasa/sites-nodejs/oxygen-free-copper/server.js
www-data 2138058  0.0  0.0   2608   528 ?        S    16:59   0:00 sh -c ps -aux | grep node
www-data 2138060  0.0  0.0   3304   716 ?        S    16:59   0:00 grep node